[asterisk-bugs] [DAHDI-linux 0015252]: [patch] procfs in dahdi can produce wrong (broken) data and warning

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15252 
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Reported By:                biohumanoid
Assigned To:                sruffell
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Project:                    DAHDI-linux
Issue ID:                   15252
Category:                   dahdi (the module)
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     closed
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             2009-06-02 06:11 CDT
Last Modified:              2009-06-04 16:17 CDT
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Summary:                    [patch] procfs in dahdi can produce wrong (broken)
data and warning
Description: 
/* In Linux 2.6, this MUST NOT EXECEED 1024 bytes in one read! */
It's not truth...

/* In Linux 2.6, page is always PROC_BLOCK_SIZE=(PAGE_SIZE-1024) bytes.
 * 0<count<=PROC_BLOCK_SIZE . count=1 will produce an error in
 * vsnprintf ('head -c 1 /proc/dahdi/1', 'dd bs=1').*/

head -c 10 /proc/dahdi/1 or if you have a lot of channels, you will see
the following:
May 25 15:48:28 asteroid kernel: [  722.051812] WARNING: at
lib/vsprintf.c:609 vsnprintf+0x38/0x452()
and a broken output...

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 (0106030) sruffell (administrator) - 2009-06-04 16:17
 https://issues.asterisk.org/view.php?id=15252#c106030 
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Eerie timing...I ran into this again for the first time after making the
original change to snprintf (I'm guilty), and then saw this issue. 
Anyway...hopefully after 2.2.0 is out, we'll see some movement towards
sysfs. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-06-04 16:17 sruffell       Note Added: 0106030                          
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